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The interface is rarely exposed to customers, though. > * In-line checksums in the database block; this approach is fairly > common for enterprise databases Yep. Also note that DIX/T10 PI are intended to prevent writing corrupted buffers or misdirected data to media. I.e. at WRITE time. Neither DIX, nor T10 PI offer any torn write guarantees. That's what the dedicated atomic write operations are for (and those do support PI). In-line application block checksums are a solution for the problem of determining whether a database block read from media is intact. I.e. in-line checksums are effective at READ time. -- Martin K. Petersen Oracle Linux Engineering